The overall goal of this project is to develop high affinity, highly selective, synthetic receptors for small organic molecules. A combinatorial chemistry approach will be used to produce an encoded, highly diverse, novel type of receptor library, whose basic structure consists of three peptide arms symmetrically arranged about a rigid hydrophobic pocket. This library could be screened for the ability to bind to a wide variety of target molecules in a wide variety of solvent systems of interest. Such receptors would serve as substitutes for monoclonal antibodies in affinity chromatography, ELISA assays, and biosensor applications. As a test case of this idea, we will screen the encoded library for receptors which selectively bind taxol in the presence of baccatin III. Selected receptors will be resynthesized and further characterized. PROPOSED COMMERCIAL APPLICATION: These synthetic receptor libraries are not designed to bind a specific target molecule. They could be screened for the selective binding of any molecule of commercial interest. Resulting specific receptors could be manufactured to furnish affinity chromatography supports, receptor-functionalized microtiter plates for ELISA, receptor-functionalized membranes or crystals for biosensors, or soluble receptor for use in drug delivery schemes.